Conventionally, an operator checks an entire layout of parts automatically arranged over a plurality of sheets according to automatic nesting. If found a low-yield sheet, the operator conducts optimization by manually rearranging parts with the use of parts moving and copying commands.
For example, a high-yield layout of parts PX and PY shown in FIG. 9 is unachievable by automation. If such parts PX and PY are automatically nested, a low-yield layout will be made, and therefore, the operator has to manually arrange the parts PX and PY.